Fluttering in any part of the body, without any previous medical condition is normally due to localized muscular hyperactivity.

So, the cause of your problem is just muscular. For this you need not to worry. Just take a course muscle relaxant like chlorzoxaxone twice a day for 3 days. Please get this prescribed from your physician.

Don’t worry, you will be all right. It’s just a benign and very common condition.

Hope, this will help you and I am ready for future follow-ups (if any).